Good grief!
Excellent!!
The obvious question: what DID you put on it? In vague detail, if it is a special secret mix, would be fine!
Well done indeedy!
At first, I wasn't doing much with the plant. In the beginning of the year I just spread some Espoma Garden-Tone. I gave some seeds to a friend in Dutchess County, New York. His plant was about 4 feet taller than mine by the end of June; so I had to do something to catch up. I then started taking it seriouly and started pouring 32 oz. to 64 oz. a week of Espoma Bio-Tone Starter on the plant. (Bio-Tone Starter is just basically the good bacteria and fungus you find in the soil) Within a few weeks of doing that, it grew an additional 5 feet in two weeks, surpassing my friend's plant. While it was growing, I was also adding a small amount of calcium nitrate 3 to 4 times a day. When mid-August came the night temps started dropping; so I started pouring hot water (3 to 4 gallons w/ the calcium nitrate in the water) on the ground 3 to 4 times a day to keep the soil temperature as high as possible. 90 degree range is optimum for nutrient uptake. It's a marsh plant; so you don't have to worry about over watering. I did a few other things, but that is mainly what I did.
My friend's plant ended up being about 22 feet, and my plant was 23 feet. However, my friend's plant grew a very large stem. His stem circumference is now over 4 1/2 feet. I don't have that because I purposely planted my very close to avoid that. My thought was I didn't want it to grow out, but up instead.
Here are pics of my friend's amaranth
picture of my friend's amaranth stalk (has grown since I took this pic)